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arXiv · 2601.18039

Quaternities, correspondences, and tetrahedron equations (Summa tetralogiae)

Gleb Koshevoy·Vadim Schechtman·Alexander Varchenko
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Abstract

The aim of this note is: (a) to propose a generalization of tetrahedron equations from \cite{S} and of their solutions. Due to appearance of a larger number of parameters the $R$-matrices from \cite{S} will be replaced by "$R$-correspondences". (b) To rephrase these equations in terms of Wronskian evolutions in the spirit of \cite{SV}. (c) To discuss some elementary structures of cohomological flavour lying behind our considerations. We call them "quaternities", or "bibitorsors"; they might be not without an independent interest.

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Gleb Koshevoy, Vadim Schechtman, Alexander Varchenko. 2026-01-25. Quaternities, correspondences, and tetrahedron equations (Summa tetralogiae). https://arxiv.org/abs/2601.18039

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